Medical sterilization apparatus



Nov. 4, 1969 H. R. LEEDS 3,476,507

MEDICAL STERILIZATION APPARATUS Filed July 16, 1967 STERILIZING I GAS \L v g 22 3 so Fig. 2

Fig.3

23 CONTACT LENS 23 INVENTOR. H.R.LEEDS BY I ATTORNEY United States Patent US. CI. 21-91 7 Claims ABSTRACT OF THE DISCLOSURE Medical sterilization apparatuscomprising a scalable container for receiving the element, such as contact lens, to be sterilized. The container is provided with a forceresponsive value which can be opened to allow a sterilizing gas to pass into the container: The gas is provided in a pressurized canister having a force-responsive valve which can be opened to allow the gas to leave the canister. The container and canister valves are so constructed that when engaged, the canister valve first causes opening of the container valve, which then causes'opening of the canister valve allowing the gas to flow directly from the canister into the container. The container is provided with means for indicating the presence of gas within it.

This invention relates to medical sterilization apparatus.

There is a need in the art for portable apparatus of small size and weight by which medical elements, instruments, apparatus and the like can be readily sterilized. A case in point is contact lens,which should be removed each night and sterilized prior to reuse the following day. Present techniques of boiling in water or immersion in sterilizing fluid are cumbersome and unreliable. Ethylene oxide is known as a sterilizing gas which when maintained in contact with the element to be sterilized for a minimum length of time will produce the degree of sterilization required. In my prior copending application, Ser. No. 630,421, filed Apr. 12,1967, I describe one form of convenient inexpensive apparatus for obtaining the required time of contact. It comprises a pressurized canister of the sterilizing gas and a scalable container for receiving the element to be sterilized. The container and canister are provided with valves constructed to engage one another in such manner that the container valve is opened prior to opening of the canister valve so that the sterilizing gas can flow directly from the pressurized canister into the container. I also describe in my copending application a wall construction of the container which indicates when a sufficient quantity of the sterilizing gas has been introduced.

The chief object of the present invention is sterilization apparatus with improved indicating means for indicating when a suflicient quantity of the sterilizing gas has been introduced.

In accordance with the present invention, the container wall is provided with an opening sealed off by a flexible gasket constructed to be movable within the wall opening in response to gas pressure within the container.

The invention will now be described with greater detail in connection with the accompanying drawing, wherein: FIG. 1 is a cross-sectional view of one form of apparatus in accordance with the invention; FIG. 2 is a top view of the container of FIG. 1; FIG. 3 is a top view of the container lid gasket.

FIG. 1 shows the container and pressurized canister of one form of sterilization apparatus in accordance with the invention. The canister 1 and container are both in cross-section in the pre-engagement position. Both devices are circular-symmetric and are drawn approximately to scale. The canister 1 is similar to the one de- 3,476,507 Patented Nov. 4 1969 scribed in my copending application and comprises a metal housing 2 containing ethylene oxide sterilizing gas 3 under pressure. It includes a force-responsive valve 4 including a nozzle 5 having a tubular channel 6 for flow of the gas 3. Movable within the channel 6 is a cylindrical piston or pin 8 which is enlarged at its top end to form an annular tapered sealing rim 9 and a recess 10 for receiving one end of a heavy compression spring 11. The sealing rim 9 bears against an annular gasket 12 of soft metal, such as lead or aluminum, which is nonpermeable to the gas. If desired, the gasket 12 may be of rubber. To reduce leakage, a cap (not shown) having a gasket on its interior, may be screwed via the threads 7 onto the nozzle 5 so as to seal oif its end. The gasket 12 is secured in place by a holder 13 which is force fitted into the nozzle 5 which seals ofl? the end of thecan 2. The holder 13 also serves to support the other end of the spring 11. A hole 14 in the holder 13 allows the gas to flow out. Grooves 15 in the inside walls of the nozzle 5 allow the gas to flow out when the pin is pushed inward. Normally, the spring 11 force urges the sealing rim 9 against the gasket 12 confining the gas within the canister 1. Should the pin be pushed inward, the gas will flow out under pressure through the channel 6.

The container 20 comprises a housing 21, for example of glass or metal, with a lid 22. The rim of the housing is threaded and the rim of the lid 22 is likewise threaded so the parts may be separated, the element, such as contact lens 23, placed within the container 20, and the lid screwed down tight sealing the interior by means of a non-permeable gasket 24 of a resilient material, such as ethylene, propylene terpolymer. Secured to the lid 22 is a valve assembly 25. It comprises, similarly to the valve 4 of the canister 1, a housing member 26 to which is secured as by internal threads for example a spring holder 27 whose upper rim sealingly engages a nonpermeable soft metal gasket 28. Within the valve is similarly arranged a slideable piston or pin 29 having an annular sealing rim 30 also engaging the gasket 28. A light compressive spring 31 is mounted between the pin 29 and the holder 27 and urges the pin against the gasket 28 to seal off the container interior. Mounted inside the gasket is a second resilient gasket 32, which may be of rubber, for engaging the nozzle 5 on the canister.

The operation of the assembly is similar to that described in my copending application. The canister 1 is moved downward. The nozzle end 5, which has an outside diameter which will engage the rubber gasket 32 to seal oif the outside and an inside diameter which will receive the container pin 29, which has the same diameter as the canister pin 8, is further dimensioned so that the pins 8 and 29 engage after the nozzle 5 engages the rubber gasket 32 and before the end engages the pin shoulder 33. Since the spring 31 is lighter than the spring 11, further downward movement of the canister 1 pushes the pin 29 down opening the container valve 25. The pin body 34 will move downward until stopped by the holder 27. Further downward movement of the canister 1 will then urge its pin 8 upward opening its valve and allowing the pressurized gas to flow from the canister 1 through both valves directly into the container 20. The downward movement of the canister 1 is stopped when the nozzle end 7 engages the pin shoulder 33. The pressure of the canister 1 is continued until the desired gas pressure is established within the container 20.

A feature of the present invention is to provide indicating means on the container wall so that when the required pressure is attained a visual indication is given. This is accomplished by forming a hole 50 in the lid and providing a protuberance 51 on the gasket 24 which projects into the opening 50'. The gasket 24 is molded with a small depression 52 at the area of protuberance 51, which is dimensioned so that the tip of the protuberance 51 is approximately level with the outer surface of the lid 22. When sufficient gas is introduced into the container, the gas pressure forces the protuberance upward against the oblique walls of the opening 50 causing the protuberance tip to project through the opening 50 above the lid level as shown in phantom in FIG. 1, thus giving a visual indication by its movement of the existence of adequate gas pressure within the container. Then the canister 1 is withdrawn closing first its valve 4 and then the container valve 25 rescaling both devices automatically. To prevent leakage around the gasket 24 through the hole 50, the spring holder 27 is provided with an annular sealing rim 55 for sealingly engaging the inner periphery of the gasket 24.

The construction shown will maintain the contact lens 23 in the sterilizing gas atmosphere for a sufficient time to obtain adequate sterilization. Leakage through the seals however does occur albeit at a slow rate, and after a period of several hours the gas pressure will reduce allowing the lid 22 to be removed for withdrawing the non-sterilized contact lens. Earlier removal is possible by simply depressing the pin 29 to release the gas. It is understood that other sterilizing gases, vapors, or suspensions under pressure can obviously be substituted for the ethylene oxide.

While I have described my invention in connection with specific embodiments and applications, other modifications thereof will be readily apparent to those skilled in this art Without departing from the spirit and scope of the invention as defined in the appended claims.

What is claimed is:

1. Medical sterilization apparatus comprising a sealable container including a housing having walls and an outer removable lid removably mounted on said walls, said container comprising a valve assembly releasably sealing the container interior, an annular resilient sealing gasket interposed between the housing walls and the lid and under the later when the lid is mounted on the housing and sealing the two together along its outer periphery, and an opening in a lid portion opposite the gasket and spaced from the housing walls, said resilient gasket having a resilient protuberance at a location opposite the lid opening and visible through the opening from the outside and dimensioned to pass through the opening, whereby the presence of gas pressure within the container urges the gasket protuberance upward through the lid opening as a visual indication of the presence of said gas pressure within the container.

2. Medical sterilization apparatus as set forth in claim 1 wherein the container valve assembly is mounted in the center of the removable lid.

3. Medical sterilization apparatus as set forth in claim 2 wherein the container valve assembly comprises a projecting housing havingan opening in a wall portion thereof and within the-assembly behind the wall portion a second annular sealing gasket surrounding but spaced from the opening, the: container valve assembly further comprises an elongated pin accessible through the said housing opening and :having an enlarged portion forming a sealing rim engaging the second gasket, a third resilient gasket islocated behind the said wall portion adjacent the housing opening, and spring means in the valve assembly urging the pin sealing rim against the second gasket. 7

4. Medical sterilization apparatus as set forth in claim 1 wherein the container valve is removably mounted on the lid and engages an inner portion of the resilient gasket which extends between'it and the lid sealing the two together.

5. Medical sterilization apparatus as set forth in claim 4 wherein the resilient gasket is constituted of a flexible synthetic resin.

6. Medical sterilization apparatus as set forth in claim 1 wherein the valve assembly comprises an annular sealing rim sealinglyengaging the inner periphery of the resilient gasket inside of the protuberance.

7. Medical sterilization apparatus as set forth in claim 1 wherein the resilient gasket has at the area of the protuberance a small depression dimensioned such that the upper tip of the protuberance is approximately level with the outer surface of the lid in the absence of gas pressure within the container, whereby with gas pressure present the protuberance projects above the level of the lid.

References Cited UNITED STATES PATENTS 95,323 9/1869 Chesley 73-408 XR 687,253 11/1901 Morgan 141-351 XR 1,200,640 10/1916 Morris 116-117 2,002,883 5/1935 Deming 116114.15 2,565,872 8/1951 Melsheimer 141-351 2,827,122 3/1958 Clark 116-11417 XR 2,965,936 12/1960 Kaye 21-91 3,037,656 6/1962 Humphrey 220-66 XR FOREIGN PATENTS 1,001,332 8/1965 Great Britain.

MORRIS O. WOLK, Primary Examiner D. G. MILLMAN, Assistant Examiner U.S. Cl. X.R. 

